Some changes were done in LSystems to be able to render 2d:
* Introduced Turtle namespace containing everything needed for turtle rendering, including Turtle.InterpretAttribbute which allowed to tag “interprtetation” methods.
* Added IRewritingRules interface which allows SystemDefintion to define rewriting rules (direction, depth, etc.).
* Some other small fixes and modifications.

It is also possible to open in the Viewer any C# file containing class or classes derived from LSystems.SystemDefinition or LSystems.Turtle.SystemDefinition (use “…” button to open a file). Opened file will be “watched” and source code will be reloaded (LSystem rebuilt) every time when file is modified. I took most of source code which compile an external file from this Phil Trelford’s post.